Automotive vehicles are commonly equipped with passenger restraint and crash mitigation devices such as seat belts, front air bags, side air bags and side curtains. These and other devices may be deployed in the event of a collision with the host vehicle to mitigate adverse effects to the vehicle and the occupants in the vehicle. With respect to activated devices, such as air bags and side curtain bags, these devices generally must be deployed quickly and in a timely fashion. Typically, these types of devices are deployed when sensors (e.g., accelerometers) mounted on the vehicle sense a severe impact with the vehicle.
In some vehicle driving situations, it is desirable to determine the onset of a collision, prior to impact of an object with the host vehicle. For example, vision systems employing cameras may be used to monitor the surrounding environment around the vehicle and the video images may be processed to determine if an object appears to be on a collision path with the vehicle. However, visions systems are generally very expensive and suffer a number of drawbacks.
An alternative approach is disclosed in U.S. Patent Application Publication No. 2009/0099736, assigned to the assignee of the present application. The approach set forth in the aforementioned patent application discloses a vehicle pre-impact sensing system that transmits a plurality of infrared (IR) beams and receives a plurality of beams within a plurality of curtains incrementally spaced from the host vehicle for sensing objects that may impact the side of the host vehicle. The aforementioned published patent application is hereby incorporated herein by reference.
It would be desirable to provide for an enhanced cost-effective system that senses a collision prior to impact with the host vehicle, particularly for use to detect side impact events.